||A simulation-based learning environment provide system designers and operators with an appreciation of the impact of incidents on traffic delay. We used SimPLE (Simulated Processes in a Learning Environment) which uses dynamic simulations and visualizations to represent realistic time-dependent behavior. Guidance material and other software aids facilitate learning. The simulation allows learners to close freeway lanes and divert traffic to an arterial road. Users can see the effect of the detour on freeway and arterial delay. Users can then adjust signal timing interactively on a time space diagram and watch the effect of their adjustment on green band changes and on arterial delays and total delays.